The invention describes a pesticidal strain of a new species to be called Yersinia entomaphaga that is active against a wide range of insect species. The novel bacterium also produces a toxic filtrate component that is also useful as a biopesticide agent in the control of insect species.
A novel insecticidal bacterium isolated from a New Zealand insect is described. The bacterium is a new species residing within the genus Yersinia and has been named Yersinia entomophaga MH96. Y. entomophaga has a broad host range towards members of the coleopteran and lepidopteran species amongst others. Death occurs within 72 hours post inoculation. The infection process appears to be due to a rapid build up in the bacterial population followed by a rapid invasion of the haemocoel leading to the cadaver taking on a deliquescing black appearance. Data are provided on biochemical utilisation tests (API), DNA sequences relating to phylogenetic analysis encompassing 16s ribosomal RNA sequencing and MLST sequence analysis of known Yersinia genes is given. In addition the DNA sequence of ˜132 short random Y. entomophaga genomic sequences are given.
A gram-negative bacterium was isolated from an infected grass grub field collected from New Zealand soils. Inoculation of grass grub larvae with the bacterium showed that death occurred within 2-3 days at 15° C. Standard biochemical identification using API20E and API50CH test strips indicated the bacterium is a member of the Enterobacteriaceae most similar to E. sakazakii, but subsequent molecular characterisation placed it in the genus Yersinia. 
The continued use of B. thuringiensis and derivatives as a biopesticide over many years can lead to an increase in resistant insects. There is, therefore, a need for novel biopesticides to control insects.
There is also a need for biological control agents such as biopesticides to provide an alternative to chemical pesticides which can be toxic to non-target organisms in the environment.
All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.
It is acknowledged that the term ‘comprise’ may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term ‘comprise’ shall have an inclusive meaning—i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term ‘comprised’ or ‘comprising’ is used in relation to one or more steps in a method or process.
It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.
Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.